1. Field of the Present Invention
The present invention is in the field of data processing systems and more particularly in the field of conserving power in data processing systems.
2. History of Related Art
Historically, power consumption and operating temperature in data processing systems have been subordinate to system performance (i.e., speed) as design considerations. More specifically, these parameters were largely considered significant only in terms of the extent to which they constrained system design and prevented the system from achieving its performance goals. Increasingly, however, power consumption and temperature concerns are becoming as important to customers as computing power. Simultaneously, server machines have evolved from more-or-less statically partitioned boxes to fully virtualized systems in which a single physical box, including the system memory, processors, and computing resources, can be allocated to virtualized machines as the customer desires. Virtualization facilitates server consolidation, which is a desirable objective for many customers.
Because system memory is a significant consumer of power and producer of heat in data processing systems, it would be desirable to implement power management techniques able to manage system memory power consumption. In a virtualized server system, it would be still further desirable if the ability to manage system memory power consumption “spanned” the virtual systems that comprise the server.